Motor vehicles that comprise a rear access panel that is guided at the bottom in hinges, by way of which it can be pivoted out of a substantially vertical closed position into a horizontal open position, are known in the existing art. In the open position, the rear access panel surface that is then at the top lies flush with the floor of the rear compartment of the vehicle.
In order to limit the pivoting angle of the rear access panel, wire segments that are attached with their free ends in the upper region of the vehicle's body are provided on both sides of the rear access panel. “Wire segments” are also to be understood here as those segments that constitute, for example, cables or other flexible (and thus windable) strands. The wire segments run through openings in the upper corners of the rear access panel to a storage spool arranged centeredly in the interior of the rear access panel. Upon opening of the rear access panel, the wire segments unwind from the storage spool synchronously and at the same speed, until the open position of the rear access panel is reached. The storage spool locks when that position is reached, with the consequence that the rear access panel cannot be pivoted any farther downward.
In the existing art, the two wire segments are part of a single, continuous length of wire that is wound in coiled fashion around the storage spool in such a way that the two wire segments are synchronously unwound in the context of a rotary motion of the storage spool in one rotation direction, i.e. in the case of opening of the rear access panel, and are synchronously rewound in the context of a rotary motion of the storage spool in the other rotation direction, i.e. in the case of closing of the rear access panel. A spring return system ensures that the two wire segments remain tensioned in every position of the rear access panel, and opening of the rear access panel occurs against the action of the spring return system.
The fact that the wire segments are parts of one continuous length of wire makes installation of the length of wire complex and labor-intensive. In addition, it is necessary for the length of wire to be accurately adjusted on the storage spool so that the extended wire segments are always of the same length. The danger nevertheless always exists that the length of wire will slip on the storage spool, with the consequence that the wire segments to be extended and retracted become unequal in length. Damage to the rear access panel can result therefrom.
U.S. Pat. No. 5,531,498 discloses an actuation device for an upwardly openable rear access panel. The actuation device has gas springs, provided on both sides, which are designed with sufficient strength that upon opening, the rear access panel pivots completely into a pivoted-up final position solely as a result of the gas springs. Also associated with the actuation device is a closing device by means of which the rear access panel can be pivoted back downward into its closed position. The closing device comprises two wire segments whose free ends are fastened on the body of the motor vehicle and extend to a storage spool arranged on the rear access panel. There the wire segments are wound on in such a way that upon a rotary motion of the storage spool in one rotation direction, both wire segments are synchronously unwound, and upon a rotary motion of the storage spool in the other rotation direction they are synchronously rewound. The storage spool is driven by an electric motor that is activated when the rear access panel is to be closed. The storage spool is then rotated in such a way that the wire segments are rewound onto it.
The wire segments are not part of a continuous wire, but rather are separate from one another and are fastened with their storage-spool ends on the storage spool by means of enlarged ends engaging into corresponding recesses. Such storage spools are also known from DE 197 41 691 A1.